Muffler for fired heater autoclave system



March 2, 1965 J. B. KLINGEL' MUFFLER FOR FIRED HEATER AUTOCLAVE SYSTEM 2Sheets-Sheet 1 Original Filed June 30, 1960 J llll l wt mm mm w a 9MEkaxim mm 1 1 ubmk mm 1 I EQQEQS P 2|! INVENT 'OR. Jafm E 1512' ngeZATTORNEYS March 2, 1965 J. B. KLINGEL 3,171,507

MUFFLER FOR FIRED HEATER AUTOCLAVE SYSTEM Originlf'iled June so, 1960 2Sheets-Sheet 2 6 3i f h INVENTORZ J 15115112158 Qwp/MW United StatesPatent ce 3,171,507 MUFFLER FOR FIRED HEATER AUTUCLAVE YSTEM John B.Kiingel, Titusviiie, Pa, assignor, by mesne assignments, to StruthersScientific and International Corporation, New York, N.Y., a corporationof Delaware Original application .iune 3t 1960, Ser. No. 37,343. Dr-

vided and this application Nov. 21, 1961, Ser. No.

3 Claims. (Cl. 131-69) The present application is a division of mycopendin'g application, Serial No. 37,343, now abandoned, filed June 30,1960, for Fired Heater Autoclave System.

This invention relates to autoclaves and a method of operating the same.The invention is of particular utility in the curing of concrete blocksand the description herein will refer specifically to such but it is tobe understood that the invention is not so limited. The essentialfeatures of the invention may be employed in the steam treating of otherarticles.

In general the invention comprises both method and apparatus and whereinan autoclave system is provided with a storage tank adjacent theautoclave. The autoclave itself is provided with a dam at the door endto retain water in the bottom thereof of sutficient depth to cover pipecoils also in the bottom of the autoclave chamber. These coils aresupplied with hot oil or other fiuid medium, heated at some externallocation, whereby the water in the bottom of the autoclave is heated andvaporized to build up the desired steam pressure and to hold thatpressure for the predetermined cycle time for the particular articlesbeing treated or cured. During the holding cycle steam condenses on thesides of the autoclave and on the equipment and material therein andmerely runs down to the bottom thereof where it is again vaporized bythe heating coils. At the end of the cycle time a valve is openedproviding communication between the upper portion of the autoclave andthe storage tank previously mentioned. This equalizes the pressure inthe autoclave and the storage tank, which in the case of curing concreteblocks is of the order of 150 p.s.i. The Water in the bottom of theautoclave is at a temperature of about 365 F. When the pressure isequalized in the autoclave and storage tank a pump is operated to pumpthe hot pressurized water from the autoclave into the storage tank, andthe previously described valve is then closed to seal the storage tankand retain pressure therein. A vent valve communicating with theautoclave is then opened to relieve pressure and exhaust the remainingsteam therefrom. The vented steam is directed into a novel mufiiertunnel which will be described in greater detail later.

After the pressure in the autoclave is reduced to atmospheric the doorthereof is opened and the cured blocks removed. The autoclave is thencharged with a fresh batch of blocks to be cured and again closed. Thepump previously referred to is then operated to pump hot pressurizedWater from the storage tank into the autoclave and since the water is ata high temperature and pressure, when it enters the autoclave atatmospheric pressure, it immediately lashes into steam. Circulation ofthe heating medium through the water in the bottom of the autoclave isagain started and the previously described cycle is repeated.

In the curing of concrete blocks a substantial amount of water isintroduced into the system by evaporation from the blocks themselves.This water also collects in the bottom of the autoclave where itoverflows a level control dam and is discharged or collected for reuse.A suitable liquid level control is provided in the autoclave 3,1715%!Patented Mar. 2, 1965 to replenish the water therein if it should fallbelow the desired value.

The novel system described briefly above offers many advantages. Thefired heater for heating the oil or other heat transfer medium operatesat a low pressure and since the autoclave itself is an unfired pressurevessel, a licensed fireman or stationary engineer is not required. Nohigh pressure boiler is used. In localities where Water is expensive atconsiderable savings results in the recovery and reuse of condensate andthere is no need for feed water treatment or preheating since any scalecollects on the outside of the heating coils or the inside of theautoclave and such scale cracks due to differential expansion andcontraction and is easily removed. However, the water may beeconomically treated chemically, which would otherwise be too expensive,and thus eliminate or minimize rack corrosion. The recovery and reuse ofcondensate permits a very substantial heat conservation with subsequentsavings. If desired, blowdown steam can also be condensed and recovered.

It is therefore an object of this invention to provide a method ofoperating an autoclave system which results in the conservation of heatand Water and a substantial acceleration of the cycling time.

Another object of the invention is to provide a method of operating anautoclave system that is highly economical and reliable in operation.

Still another object of the invention is to provide a method andapparatus in an autoclave system whereby hot condensate is stored forreuse in a subsequent cycle.

A further object of the invention is to provide, in an autoclave system,a novel mufiier device to eliminate undue noise and disturbance uponblowdown.

Still further additional objects and advantages will become apparent tothose skilled in the art as the description proceeds with reference tothe accompanying drawings, wherein:

FIG. 1 is a diagrammatic plan view of an autoclave system according tothe present invention;

FIG. 2 is a diagrammatic side view of the apparatus shown in FIG. 1;

FIG. 3 is an enlarged transverse sectional view taken substantiallyalong the line 3-3 of FIG. 1;

FIG. 4 is a further enlarged fragmentary sectional view taken along theline 4-4 of FIG. 3;

FIG. 5 is a vertical sectional View through the muffler tunnel and takenalong the line 55 of FIG. 1;

FIG. 6 is a horizontal sectional View taken along the line d6 of FIG. 5;

FIG. 7 is a fragmentary sectional View taken along the line 7-7 of FIG.5; and

FIG. 8 is an enlarged fragmentary section taken along the line 8-8 ofFIG. 5.

With reference particularly to FIGS. 1 and 2, a more or lessconventional autoclave 2 is shown which comprises a tank-like structuredefining a pressure chamber having an openable sealing door 4 at one endthereof.

Inside the chamber 2 are tracks 6 (see also FIG. 3) upon which cars orcarts may be rolled to load and unload the autoclave with the articlesto be treated. A pipe 8 is arranged along the bottom of the autoclavechamber and, as shown, is sinuously arranged therein but may be arrangedin parallel lengths connected to common headers at their ends. Any othersuitable arrangement, however, could be employed and applicant willherein use the term coil to refer to the pipe 8.

As shown in FIGS. 3 and 4, the autoclave is provided with a transversedarn 10 defined by an upright plate of steel or the like at the endthereof near the door 4. The dam 10 extends to a sufficient height toretain Water in the bottom of the autoclave to a level sufficient tocover the coil 8. It is to be noted that the Water level is below thelevel of the tracks 6. The tracks 6 are mounted on spaced blocks or thelike 12 providing a space therebetween to permit condensate to run downthe inside surface of the autoclave to the bottom thereof.

The forward end of the coil 8 is connected through a conduit 14 to asuitable heater 1.6. The conduit 14 is provided with a valve 13 therein.As diagrammatically shown in FIGS. 1 and 2, the heater 16 is fed by apump 20 through a conduit 22 from a supply of oil or other heatingmedium in an expansion or supply tank 24. The expansion tank 24 isconnected, through conduit 26, to a fitting 23 at the rear end of theautoclave and an internal conduit (not shown) connects the fitting 28 tothe rear portion of the coil 8, thus defining a closed circulationsystem. It is obvious that, with valve 13 open and pump operating, oilis pumped into the heater where it is heated to the high temperaturenecessary and thence through the coil 8 where it heats the water held inthe autoclave by the dam 10. The oil circulates through the coil 8 andfitting 2%, thence through conduit 26 back to the pump 2%, the inletside of which is in communication with the expansion tank 24.

A condensate storage tank Fall is provided adjacent the autoclavechamber 2 and the upper portion of tank 313 is connected through conduit32 to the upper portion of the autoclave 2. A selectively operable valve34 is provided in the conduit 32.

A pump 36 having an inlet 38 and an outlet 40 (see FIG. 1) is connectedthrough the piping shown to the tank 39, the bottom portion of autoclave2 and to a source of makeup water, not shown. By manipulating the valves42, 44, 46, 4S and 5b, in a manner to be described, the pump 36 may beoperated to pump condensate from autoclave 2 into tank fall, to pump thewater from a source of makeup water either into the autoclave 2 or intothe condensate tank 30, all as will be described in greater detail.

A vent conduit 52 communicates with the interior of the autoclave, atthe bottom thereof, and is provided with a vent valve 54. The ventconduit 52 terminates in one end of a muflier tunnel indicated in FIGS.1 and 2 generally by the numeral 56.

Referring now to FIGS. 5 through 8, the muffler tunnel comprises anelongated passageway having transverse dimensions quite large relativeto the transverse dimension of the vent pipe 52. The tunnel comprises agenerally horizontal portion 58 and a generally vertical or stackportion 6t). The horizontal portion $8 is provided with a plurality oftransverse bafiles 62 therein. The bafiles' 62 extend from alternatesides of the passageway and each terminates short of the opposite side,as clearly shown inFIG. 6. Each of the batiies 62 may be constructed ofconcrete blocks having their usual core openings 64- extendinghorizontally to define somewhat restricted passageways through thebafiies. Adjacent the juncture of the horizontal portion 58 and thestack portion 69, a transverse partition wall d6 is provided to supporta wall portion of the stack 6t thereover. The wall 66, however, may beformed of concrete blocks having their core openings d4 extendinghorizontally to provide a flow path for exhaust steam from thehorizontal portion into the stack portion. Within the stack portion atransverse imperforate partition wall 68 is provided terminating somedistance below the upper end of the stack. Spaced from the partitionwall 63 is a further vertical partition 70 which is imperforatethroughout its upper portion but formed of concrete blocks at least atits lower end, the concrete blocks thereat being arranged with theircore openings extending horizontally to define a'flow path through thebottom portion of the partition '70. The partition 7d extends upwardlywithin stack till to a greater height than the partition 68 and a capplate 72 spans the space from the upper end of partition '70 to theforward wall of the stack (all and is in overlying but spaced relationto the upper end of partition 68. As will be evident from the abovedescription and inspection of the drawings, the horizontal portion ofthe Inufller passageway having the baflles therein defines generallysinuous flow paths for exhaust steam. The steam then passes through thewall 66 and along the sinuous flow path indicated by the arrows in PEG.5 to the upper end of the stack where it exhausts to atmosphere. Thesinuous fiow path within stack 6h has upwardly and downwardly extendingportions, whereas the flow path in the portion 58 is a horizontallyundulating flow path.

Due to the nature of the how path provided Within the mufilerpassageway, the restricted openings through which the steam must pass,and the fact that the transverse dimensions of the passageway are quitegreat relative to the diameter of conduit 52, a highly efficientrnutliing of the exhaust is achieved. It is well known that pressurizedsteam, when exhausted directly to the atmosphere, expands rapidly andcreates very loud noise which may be highly disturbing, and in someinstances dangerous, to all within the vicinity thereof. By means of themufller tunnel herein described, the autoclave 2 may be vented quiterapidly without creating an undue disturbance.

Below the stack portion till a drain pit or channel '74 is formed. Adrain opening 76 is formed in the floor or bottom 78 of the mothertunnel whereby moisture condensed within the tunnel may be drained away.FIG. 8 shows an enlarged detail of the bottom portion of the imperforatepartition wall 68 and shows a drain opening 89 formed therein to permitflow of anycondensate from the horizontal portion 58 or from the spacebetween partition 6S and the adjacent stack wall to drain toward drainopening 76. If desired, the bottom 78 may be formed to slope towarddrain opening '76. i

In first starting the system for its initial cycle of operation, theheater 16 is fired to start heating the oil therein. Valves 4-2., 44 and48 are closed, as are the valves 18 and vent valve 54 along withequalizer valve 34. The pump 36 is then started with valves 45 and 5!being open, to pump an initial supply of water into the autoclave 2. Itis assumed that the autoclave has been charged with con crete blocks tobe cured and the door 4 remains open. When the level of the waterreaches the top of the dam ll), as determined visually, valves 46 and 5dare closed, pump 36 is stopped, and door 4 is closed and locked. It isfurther contemplated that a suitable level control device (indicatedschematically at 84 in FIG. 1) be provided to detect lowering of thewater level in the autoclave, during a cycle of operation, to too low alevel. Any overflow from the darn it), due to gain in water byevaporation from the blocks being cured, is discharged through anysuitable trap of well-known design (not shown).

When the autoclave 2 has thus been charged with the required amount ofstarting water, the valve 18 is opened and pump 20 started in operationto commence circulating hot oil through the coil 3. The hot oil heatsthe water in the autoclave to produce steam. The air trapped in theautoclave upon charging the same with the articles to be cured, isvented through suitable thermostatic vent devices 82. The vent devices82 are of conventional construction and are well known in the art. Theyremain open as long as air flows therethrough but closes when the flowof air stops and steam begins to flow out. Thus all of the air isexhausted from the autoclave by the initially produced steam and theautoclave is then sealed so that steam pressure can build up to therequired level. In curing concrete blocks it has been found desirable toheat the oil in heater 16 to a temperature of about 550 F. It is furthercontemplated that pressure control means be provided to limit the steampressure in the autoclave to about p.s.i., the water in the bottomthereof then being at a temperature of about 365 F.

When the curing pressure has been attained automatic valves (not shown)function to permit flow of only the amount of oil necessary torevaporize condensate within the autoclave, the only heat loss from thesystem being by radiation and condensation. All the steam that condenseswithin the autoclave flows to the bottom thereof and is continuouslyre-evaporated during the holding or curing cycle.

After the predetermined cycle time has elapsed and the concrete blockscompletely cured, flow of hot oil through the coil 8 is stopped byclosing valve 18 and stopping pump 20. Thereafter equalizer valve 34 isopened, which permits high pressure steam from the autoclave to enterthe condensate storage tank 30 and to equalize the pressure in the twoenclosures. After the pressure is thus equalized, valve 48 is opened toprovide communication between the bottom of the autoclave and the inletto pump 36. Valve 44 is also opened and pump 36 is started to pump allof the hot pressurized water from the autoclave 2 into the condensatestorage tank 30. After all of the water has been thus pumped into thetank 30, the valves 48 and 44 are closed, as is valve 34, to seal thetank 30 and retain the water therein at the high pressure of 150 psi. Atthis time nothing but steam is left in the autoclave 2. The vent valve54 is now opened to exhaust steam from the autoclave into the mufflertunnel already described and to reduce the pressure in the autoclave toatmospheric. Thereafter the door 4 is opened and the cured blocks areremoved for use. The autoclave is then recharged with a new supply ofblocksto be cured and the door 4 is closed and sealed before water isintroduced. The vent valve 54 is then closed and valves 42 and 46 areopened. Pump 36 is then started and pumps the stored hot pressurizedwater from storage tank 30 into the autoclave 2. The level controldevice previously referred to may be in control of the pump 36 at thistime to stop the same when the desired Water level is reached. Under thetemperature and pressure conditions described, entry of the hotpressurized water into the autoclave results in immediate flashing ofthe same into steam, due to the reduction in pressure thereon from 150psi. to atmospheric. Any air in the autoclave is exhausted through thethermal valves 82 previously described and when the required level ofwater is achieved in the autoclave, pump 36 is stopped and valves 42 and46 are again closed. Valve 18 is then opened and pump 20 is started andthe previously described cycle is repeated.

it is to be understood that, while manually operated valves have beenshown and described for the sake of simplicity, a completely automaticcontrol system of any well-known type could be employed to cause thesequence of operations herein described to be performed automatically.It is also to be understood that the tank 30, shown separate from theautoclave 2, may be an integral part thereof in the form of acompartment therein.

It is obvious that, since the heat required to hold the autoclave to therequired curing pressure is quite small, a series or bank of similarsystems may be served by the same heater 16. Such a series of systemswould have their cycles staggered so that only one of them would bestarting its cycle at a time, the remaining autoclaves being in theholding portion of their cycle and thus requiring only a small amount ofheat. The horizontal portion 53 of the muffler tunnel 5'6 would then bearranged to extend in such direction as to be accessible to all of theautoclaves in the series and would serve as a muffler for each of them.

While a single specific embodiment of the invention has been shown anddescribed herein, it is to be understood that the same is merelyillustrative, that the invention is not limited thereto but embraces allforms and modifications falling within the scope of the appended claims.

I claim:

1. In an autoclave system having means defining an autoclave chamber tohold steam therein under pressure; a vent conduit for selectivelyopening the same, means defining an elongated passageway, comprising ahorizontal and a vertical section, the transverse dimensions of the saidpassageway being large relative to the transverse dimensions of saidvent; the horizontal section of said passageway communicating at one endwith said vent and at the other end with said vertical section through aperforate wall, and containing transverse baffles extending alternatelyfrom opposite sides thereof to define a moderate sinuous fiow paththerethrough, the vertical section of said passageway being open to theatmosphere through a perforate wall and containing substantiallyimperforate vertical baffles defining an extreme vertical sinuous flowpath through said vertical section.

2. The apparatus of claim 1 wherein the transverse baflies areconstructed of concrete blocks and contain a plurality of restrictedopenings.

3. The apparatus of claim 1 wherein the vertical section of saidpassageway has an opening to a drain pit for collecting condensed steamfrom the passageway.

References Cited in the file of this patent UNITED STATES PATENTS1,186,067 Becker June 6, 1916 1,914,072 Boylston June 13, 1933 1,993,895Ploen Mar. 12, 1935 2,324,706 Jacobson July 20, 1943 2,392,247 KatcherIan. 1, 1946 2,727,584 Marx Dec. 20, 1955 2,864,455 Hirschorn Dec. 16,1958 3,018,840 Bourne et al Ian. 30, 1962

1. IN AN AUTOCLAVE SYSTEM HAVING MEANS DEFINING AN AUTOCLAVE CHAMBER TOHOLD STEAM THEREIN UNDER PRESSURE; A VENT CONDUIT FOR SELECTIVELYOPENING THE SAME, MEANS DEFINING AN ELONGATED PASSAGEWAY, COMPRISING AHORIZONTAL AND A VERTICAL SECTION, THE TRANSVERSE DIMENSIONS OF THE SAIDPASSAGEWAY BEING LARGE RELATIVE TO THE TRANSVERSE DIMENSIONS OF SAIDVENT; THE HORIZONTAL SECTION OF SAID PASSAGEWAY COMMUNICATING AT ONE ENDWITH SAID VENT AND AT THE OTHER END WITH SAID VERTICAL SECTION THROUGH APERFORATE WALL, ADN CONTAINING TRANSVERSE BAFFLES EXTENDING ALTERNATELYFROM OPPOSITES SIDES THEREOF TO DEFINE A MODERATE SINUOUS FLOW PATHTHERETHROUGH, THE VERTICAL SECTION OF SAID PASSAGEWAY BEING OPEN TO THEATMOSPHERE THROUGH A PERFORATE WALL AND CONTAINING SUBSTANTIALLYIMPERFORATE VERTICAL BAFFLES DEFINING AN EXTREME VERTICAL SINUOUS FLOWPATH THROUGH SAID VERTICAL SECTION.